Drug side effects
sulfasalazine Side Effects
The reactions most often reported to the FDA for sulfasalazine (also sold as Azulfidine), with demographics, serious outcomes, and reporting trends.
Data updated 2026-05-15
- 76,270
- FAERS reports
Data from the FDA Adverse Event Reporting System (FAERS), 2003 to 2025. A FAERS report records a temporal association, not proof of cause. See our methodology for how figures are compiled and de-duplicated.
The most commonly reported side effects of sulfasalazine come from 76,270 reports to the FDA, broken down here by frequency, patient demographics, and serious outcomes.
This page analyzes 76,270 reports to the FDA Adverse Event Reporting System (FAERS) for sulfasalazine (Azulfidine): the reactions reported most often, who reported them, serious outcomes such as hospitalization, and year-over-year trends. A FAERS report does not prove the drug caused the effect, and report volume tracks how widely a drug is used, not how likely an effect is for any one person. Educational information, not medical advice.
Total Reports
76,270
Reports Mentioning Death
6,629
8.7% of reports — not proof the medicine caused the death
Hospitalizations
20,613
27.0% of reports
Top Indication
Rheumatoid Arthritis
Most Reported Adverse Reactions
Who Reports Side Effects
Gender Distribution
Age Distribution
Reporting Trend by Year
Reactions in Death Reports
Top reactions reported in 6,629 reports where death was an outcome. These are voluntarily reported and do not establish causation.
| Reaction | Reports |
|---|---|
| RHEUMATOID ARTHRITIS | 2,082 |
| SYSTEMIC LUPUS ERYTHEMATOSUS | 2,074 |
| TYPE 2 DIABETES MELLITUS | 2,028 |
| JOINT SWELLING | 1,999 |
| SYNOVITIS | 1,970 |
| RASH | 1,961 |
| GLOSSODYNIA | 1,958 |
| WOUND | 1,945 |
| PSORIATIC ARTHROPATHY | 1,939 |
| INFUSION RELATED REACTION | 1,933 |
| PAIN | 1,910 |
| GENERAL PHYSICAL HEALTH DETERIORATION | 1,904 |
| HAND DEFORMITY | 1,874 |
| HYPOAESTHESIA | 1,874 |
| FATIGUE | 1,871 |
| FIBROMYALGIA | 1,869 |
| SWELLING | 1,847 |
| HEPATIC ENZYME INCREASED | 1,840 |
| DUODENAL ULCER PERFORATION | 1,834 |
Reactions in Hospitalization Reports
Top reactions in 20,613 reports where hospitalization was an outcome.
| Reaction | Reports |
|---|---|
| RHEUMATOID ARTHRITIS | 5,015 |
| PAIN | 4,516 |
| ARTHRALGIA | 4,487 |
| JOINT SWELLING | 4,240 |
| FATIGUE | 4,179 |
| RASH | 3,909 |
| CONDITION AGGRAVATED | 3,681 |
| SYNOVITIS | 3,637 |
| DRUG HYPERSENSITIVITY | 3,524 |
| ARTHROPATHY | 3,515 |
| NAUSEA | 3,311 |
| INFUSION RELATED REACTION | 3,271 |
| HYPERSENSITIVITY | 3,192 |
| PERIPHERAL SWELLING | 3,191 |
| ABDOMINAL DISCOMFORT | 3,184 |
| VOMITING | 3,105 |
| DIARRHOEA | 3,103 |
Nearby, Related Medications
What the FAERS Data Reveals About sulfasalazine Side Effects
The FDA Adverse Event Reporting System (FAERS) contains 76,270 voluntary reports linked to sulfasalazine and its brand equivalents (Azulfidine), spanning 2003 through 2025. Of those, 6,629 (8.7%) listed death as an outcome and 20,613 (27.0%) involved hospitalization. The most common indication reported alongside adverse events was Rheumatoid Arthritis.
Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 77% were female and 23% male; age distribution skews toward 45-64, with 20,646 reports in that bracket. The single most reported reaction is rheumatoid arthritis with 19,190 submissions, followed by pain and arthralgia.
How to read these numbers
FAERS is a signal-detection tool, not a scorecard. Reports are voluntary, and a single case may list multiple suspect drugs, so numbers above should not be read as incidence rates or per-patient risk. Widely prescribed drugs naturally accumulate more reports than niche therapies even when individual risk is low. These aggregates are useful for spotting patterns that merit further pharmacovigilance, not for choosing between medications. This page is for educational reference only and is not medical advice, speak with a licensed clinician about any side-effect concerns.
Drugs With a Similar FAERS Report Volume
Other medications with a total FDA adverse-event report count closest to sulfasalazine's 76,270.
Read our methodology - how this data is sourced, computed, and verified.